The current state of the art describes methods of performing security schemes based upon conventional computer architecture which utilize cryptographic methods. These methods are usually based upon the usage of HW secure tokens (smart cards, secure USB devices). This ensures high security of cryptographic key storage and the authorized use of cryptographic keys (PIN entry required to access token-based operations). Securing the authenticity of data entering token operations causes bigger problems. Applications utilizing external cryptographic tokens to secure data can show the client the correct data intended to be processed (such as a payment order to the client's bank), however, an unreliable computer environment cannot guarantee that the data will actually be sent to the token and processed therein in their identical form. Harmful software can modify the data and thus damage the client's interests (e.g. modify the recipient's account in the payment order or alter the amount).